The present disclosure relates to a drying device for reducing a moisture content of a gas present in an internal space of a housing, having a desiccant cartridge comprising a desiccant. In addition, a battery system and a motor vehicle having said drying device are provided.
In order to ensure the safety of battery systems, in particular lithium-ion battery systems, and to optimize the energy and performance parameters and the service life, the battery cells of the battery system are preferably operated within a defined temperature range. It is necessary, especially in the case of a high power input/output, to avoid heating of the battery cells above a specific operating temperature and to dissipate the heat occurring in operation. Cooling systems are generally used for this purpose.
In addition, it may also be necessary to heat battery cells that are too cool to a required operating temperature. A temperature control system may also be used for this purpose. To achieve the required operating temperature it is therefore preferable to use a unit which will serve both to supply heat and to dissipate heat.
Air or water is generally used as medium for cooling the battery cells, wherein the respective medium absorbs the heat and removes it from the cells. Aqueous cooling media are often led through a base plate, which is thermally connected to the battery cells, for example by way of metal sheets. When air is used as cooling medium, this is fed through between the cells. Air cooling, in particular, necessitates a relatively large preparatory outlay for dehumidification and filtering of the cooling air, and feeding the flow through the housing to the battery cells. In the case of a water-cooled battery system the particular problem arising is that of condensate forming inside the housing.
One known solution, in order to reduce the moisture or condensate accumulating in the housing, is to dry the air present in the housing by means of a desiccant.
To do this, corresponding precautions have to be taken, such as positioning the desiccant at a suitable location in the housing, for example. For this purpose the previously unpublished application DE 10 2010 028 861 shows a drying device in a housing internal space, in particular a battery housing internal space, wherein the drying device comprises a desiccant body and a fixing device for positively and/or non-positive fixing of the desiccant body, which serves for positioning the desiccant body in the housing internal space or positioning it so as to form at least a part of the inner surface of the housing.